I've personally found that I make twice as much at 10NL around 7pm GMT due to all the British and European fish coming home from work, and that I generally make much less in the early hours, due to most of the tables being multitabling nutcampers.
I saw an article on TV recently where a married couple from Luton were making there monthly mortgage payment playing $10 at Paradise from 11 pm EST to around 4 am friday and sturday- This converts to 3 am to 10 am GMT. They argued that this is the best time to go up against the "drunken Americans". The East coast is 4 hours behing the UK and the west coast is 8 therefore a session in where between those time will see you OK.

On Paradise your better off going up against druken americans than druken Europeans simply because there numbers dominate most tables. Ide be intersted to know what EST time other UK players reckon is best.

Cheers